<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      function Dog(name) {
        this.name = name;
      }
      Dog.prototype.run = function () {
        console.log(this);
        console.log("跑得很快");
      };
      //   let d1 = new Dog("小黑");
      //   d1.run();
      Dog.prototype.run();
    </script>
  </body>
</html>
